About the Alcohol Units Calculator
A unit of alcohol is a way to measure how much pure alcohol is in a drink. In the UK one unit is 10 millilitres, or about 8 grams, of pure alcohol. You can work it out from the size of the drink in millilitres and its strength, the ABV. This calculator also gives the grams of alcohol, the number of US standard drinks (14 grams each), the calories from the alcohol alone and the share of the 14-unit weekly guideline. Type the size of the drink, its strength and the number of drinks and the alcohol units appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the Alcohol Units Calculator
- 1Enter the size of the drink, its strength and the number of drinks.
- 2Pick the units or options from the menus if the alcohol units tool offers them.
- 3Read the alcohol units in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the alcohol units
People use unit counts to keep track of what they drink against health guidance. UK advice is to keep to no more than 14 units a week, spread over several days, with some days free of alcohol.
Large glasses and stronger drinks contain more than people expect: a large 250 ml glass of 13 percent wine has 3.25 units, a third of the weekly guideline. Counting units shows how quickly they add up.
How the alcohol units is worked out
UK units = volume in ml × ABV % ÷ 1,000. Grams of alcohol = volume in ml × ABV ÷ 100 × 0.789. US standard drinks = grams ÷ 14. A pint of 4 percent beer (568 ml) contains 2.27 units, 17.9 grams of alcohol and 1.3 US standard drinks, roughly 125 calories from the alcohol. A 175 ml glass of 12 percent wine has 2.1 units. A 25 ml shot of 40 percent spirit is exactly 1 unit.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- UK units and US drinks
- Grams and calories
- Share of weekly guideline
Mistakes to avoid with alcohol units
This is information, not medical advice. Guidelines differ by country and by age, sex and health. Some people should not drink at all, such as those who are pregnant or taking certain medicines. The calorie figure counts the alcohol only, not sugar or mixers.
On phone and computer
On a phone, type into the boxes one after another and read the alcohol units underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the alcohol units move. The alcohol units calculator works the same on both. Drinking affects more than units. Estimate blood alcohol with BAC Calculator, see the calories with Calorie Calculator, plan your drinks of water with Water Intake Calculator, and check your weight with BMI Calculator.
Features
- Check large glass sizes
- Guidelines differ by country
- Information only
- Clear messages when the alcohol units inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate alcohol units?
UK units = volume in ml × ABV % ÷ 1,000. Grams of alcohol = volume in ml × ABV ÷ 100 × 0.789. US standard drinks = grams ÷ 14. A pint of 4 percent beer (568 ml) contains 2.27 units, 17.9 grams of alcohol and 1.3 US standard drinks, roughly 125 calories from the alcohol. A 175 ml glass of 12 percent wine has 2.1 units. A 25 ml shot of 40 percent spirit is exactly 1 unit.
What is the formula for alcohol units?
UK units = volume in ml × ABV % ÷ 1,000. Grams of alcohol = volume in ml × ABV ÷ 100 × 0.789. US standard drinks = grams ÷ 14. The alcohol units calculator applies it exactly and rounds only the displayed answer to six significant figures.
How many units are in a pint of beer?
About 2 to 3, depending on strength. A pint of 4 percent beer is 2.3 units.
What is a standard drink?
In the US, 14 grams of pure alcohol. The definition differs by country.
How are units worked out?
Volume in ml times ABV divided by 1,000.
Is this alcohol units calculator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.